3 Jul
1999
3 Jul
'99
2:07 p.m.
At 11:28 AM 7/3/99 -0400, Allison wrote:
<Boy does that sound like spec. inflation! 24 p-p is
just 12 Volt peak in
<either polarity with a bridge circuit. That gives 12/8 peak amps and 18
<peak watts (like with a +/-12 volt square wave). The RMS voltage and
no that would be 24/4 (two speakers presuming they are parallel) or 6A.
Assumes a 100% lossless bridge amp. at 24VPP and 6A you have 144W if it's
a symetirc squarewave, less if sine(RMS).
Sorry, I cannot tell if you switched from an engineer to a marketroid ;).
In this bridge circuit with a 12 volt supply:
+12 -------
A B
.LOAD..
C D
return-----
(A, B, C, D) are switches, either A, D or B, C on,
The 4 Ohm load sees a maximum current of 3 Amps in either direction.
That is 1.5 Amps for each of two 8 Ohm speakers in parallel.
The maximum (peak) power is 36 watts, 4x that of a non-bridged amplifier.
"peak to peak power" is just a marketroid term. Actually I don't even use
the term "RMS power", as IMHO, "RMS" applies to voltage or current,
not power.
-Dave